Having a problem figuring out what size hex wrench this part takes. It’s labeled #9 at the extreme bottom right of the diagram…

2011 Yamaha GRIZZLY 700 EPS 4WD HUNTER (YFM7FGPHA) Crankcase Cover 1 | Flemington Yamaha

I have a half inch hex and that’s def not it, too small. No parts store in town has anything that size so I’m gonna have to special order.

Any idea what size driver this part takes?